Someone who hits or strikes things, or in British slang, a person who attacks others for their identity or beliefs.
From the verb 'bash' (to strike forcefully), which is likely imitative in origin, with '-er' added to mean 'one who bashes.'
The term 'basher' is particularly associated with 'queer-basher' in 1980s-90s activism—by naming the aggressor rather than victimizing language, activists reclaimed the power to define the violence happening in their communities.
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